The Siphon-Controlled Pneumatic Displacement Pump herein presented is an extension of the inventor's original theme, and was designed and developed in the hope that it can help to solve a specific world problem.
The population explosion and world-wide climatic changes have created a problem of global magnitude in which a vast number of the world's population has difficulty in obtaining a daily supply of sanitary drinking water. The World Health Organization places the daily human death rate, directly attributable to the drinking of polluted water, in the tens of thousands. A 1984 news release by Xinhau, the official Chinese news agency, reported that, in China alone, over 500 million people were drinking unsanitary surface water from rivers, ponds and shallow wells. The dangers and risks involved in the human consumption of surface water are too well known to need further elaboration. The technical reason for this forced dependence on unsanitary surface drinking water, some 200 years from the start of the Industrial Revolution, does need considerable elaboration. Unfortunately, the technical reason for the problem does not easily adapt to a brief explanation.
The basic weakness of present-day water well pumping technology that prevents its rapid transfer to lesser-developed countries is, in large degree, caused by industry concentration on pumping methods that only adapt in economic environments. common to the industrialized nations. In these relatively rich, industrialized nations, the present well water pumping technology is very efficient and very effective. The motor and engine-driven pumps produced by the industry, utilizing relatively high-speed rotating mechanical liquid displacement members, allow access to huge quantities of deep source sanitary water. These pumps, in combination with an effective surface water filtering and purification technology, account for the relative abundance of sanitary drinking water in most all of the industrialized nations. The efficiency of this combined technology is best illustrated by the fact that, on a daily basis, Americans alone dump more drinking-quality water down the sewer than would be required to sustain the 500 million Chinese people now drinking the potentially very dangerous surface water.
With conservation, the daily drinking and cooking water requirement for a family is quite small. Technical limitations inherent in existing water well pumping technology prevent its being transferred to non-industrialized rural areas of the lesser-developed countries to meet even this small requirement. The present industry concentration on well water pumps driven by engines and motors renders the technology useless if the engines, and motors are not available to drive the pumps. The low per-capita income that prevails in most of the world's non-industrialized areas dictates that the preferred method of water pumping must be either by hand or by some other form of cheap alternative energy.
The cheap alternative energy referred to here would have to be animal power when widely-separated families were involved. Other non-animal alternative energy sources are far too expensive to be applied on an individual family basis when the annual per-capita income is taken into consideration.
The average healthy male in good physical condition can produce a work output of 1/8 to 1/10 horsepower throughout an 8-hour work day. With a new and different water well pumping technology, the utilization of just a small percentage of this daily work output capability would be sufficient to provide the average family with a daily supply of sanitary water from deep water sources to meet their cooking and drinking needs. The "how" and "why" of this new and different water pumping technology can only be appreciated when it is judged alongside the existing technology as it relates to deep well water extraction utilizing fractional horsepower inputs and non-motor or non-engine driven pumps.
The only hand-powered water well pump in common use today is the piston pump which has been around for over 2,000 years and was used for water pumping by inhabitants of the Roman Empire. The piston pump can take the form of a lift pump or a force pump. The difference in the lift pump and the force pump is the piston's location in relationship to the water being pumped.
In the lift pump, the water is always below the piston and the filling of the pump cylinder is accomplished through atmospheric pressure. Because of an atmospheric pressure constraint, lift pumps cannot effectively obtain water that is 25 feet or more below the pump piston. This 25-foot lift constraint becomes even greater with an increase in altitude. ln fact, the 25-foot limit will drop to 22 feet at an altitude of 3,000 feet above sea level. Water obtained from wells 25 feet or less in depth is considered to be surface Water. Unfortunately, the vast majority of hand-operated lift pumps have the piston located above ground level and the water extracted with these pumps does not have the benefit of deep earth filtration. These common, above-ground, piston pumps readily adapt to an easily drilled 2-inch well with its relatively inexpensive well pipe. This fact accounts for their popularity in rural areas.
The force pump places the piston down the well in the water to be pumped. The force pump is very effective on deep water applications and is utilized extensively on the wind-driven pumps found on many farms and ranches. Placing the piston inside the well pipe and below ground level adds considerably to the cost of the pump. With 4-inch diameter and larger wells, and with power sources such as Wind turbines and internal combustion engines, the in-the-well piston-type force pump is practical. To, extract deep water from small diameter wells in the lesser-developed countries, the force pump, with its accompanying array of in-well components and its mechanically-connected linkage to a ground level power source, is not practical.
A very high percentage of the world's usable fresh water supply is located at depths that are less than 200 feet from ground level but greater than 25 feet. The drilling of small diameter wells to these depths is not difficult or energy intensive. The drilling can be accomplished with small machines or by utilizing the ancient method of hand pounding. The Chinese people have been pounding holes in the ground for almost 2,000 years with massive hand-lifted metal bits and they can be considered experts in utilizing this technique. Unfortunately, many useless holes were pounded into good water supplies that could not be utilized because the water Would not rise in the hole to the less than 25-foot pumping range required for a lift pump with an above-ground piston.
The recent advent of low-cost plastic pipe allows small diameter wells to be economically provided with an effective casing to seal off possible intrusion of polluted surface water.
Other recent advances in drilling technology have produced small rotary drilling machines which are easily transported and non-energy intensive. These small drilling machines have made the drilling of vast numbers of small diameter deep wells economically practical. The small machines referred to are capable of drilling a 2-inch well to a depth of 200 feet. However, if you drill a 2-inch well and the Water is down more than 25 feet, there is presently no practical way to bring this water to the surface without a motor or engine-driven pump. This limitation excludes the 2-inch well from many rural areas. It also prevents an access to sanitary water for many millions of poor people.
The Siphon-Controlled Pneumatic Displacement Pump herein presented will allow economical access to the vast stores of sanitary water available below the 25-foot level in many of the lesser-developed countries.
A study of the prior art reveals that very few pneumatic displacement pumps with an automatic cycle control have been built. One such pump, as described in U.S. Pat. No. 4,083,661, is utilized to pump sewage. In this application, a tank is placed at a low sewage collection point and, when the tank becomes full, compressed air is applied to blow the tank contents to the main sewer line having a higher elevation. Total control of the pump cycle is accomplished by a float-operated spool-type air valve located within the tank. The size, the manufacturing cost, and the confinement of the total control system within a large tank, renders this pump not practical for well water pumping in small diameter wells.
Another pneumatic displacement pump was presented in U.S. Pat. No. 4,305,700. This pump was designed to pump oil from slow-flowing and marginal oil wells. It utilizes a series of vertical blow chambers that drop into the well pipe and are connected together with pipes. The objective of this invention is to use compressed air to make a vertical stair-step type lift of the oil by means of compressed air being applied in a timed sequential sequence that progressively moves the oil upward through the blow chambers to a ground-level storage tank. Control of the blow and vent process is by means of a timing-motor driven rotary valve. The only positive control in this cycle is a float switch that prevents a restart of the timed cycle if no oil is present in the bottom blow chamber.
The inventor knows of another manufacturer in Australia who utilizes a timing motor to control a water well pumping cycle by means of a similar arrangement. A timed control of the blow cycle is not practical when utilizing alternative energy sources that produce wide variations of energy inputs to the pumping process. The specification that follows incorporates more details than would normally be required in a patent specification. The excessive detail is provided to assist the professional, as well as the lay reader, in full understanding of the invention. In the mind of the inventor, the magnitude of the problem addressed by the invention justifies this extra detail effort.
The dominating objective that resulted in the present invention was a desire by the inventor to provide an economical means to pump usable amounts of water from depths of up to 200 feet from small diameter wells using energy inputs to the pumping system that could be provided by a small child. The inventor sincerely hopes that through this invention some of the aforementioned problems can be mitigated.